Electric switch



Aug. 3, 1937.

l l l G. J. MEUER 2,089,032

ELECTRIC SWITCH Filed April 6, 1936 2 Sheets-Sheet 1 a a 28 J Z 65 4a INSULATION*Z7-% 38 51 a Aug. 3, 1937. a. J. MEUER ELECTRIC SWITCH Filed April 6, i956 2 sheets-shed 2 Y 55 @FQ M v Patented Aug. 3, 1937 PATENT? OFFICE ELECTRIC SWITCH George J. Meuer, Milwaukee, Wis., assignor to Cutler-Hammer, Inc., Milwaukee, Wis., a corporation of Delaware Application April 6, 1936, Serial No. 72,881

20 Claims.

This invention relates to improvements in electric switches, and more particularly to electric snap switches of the so-called tool-handle type.

A primary object of the invention is to provide a novel form and arrangement of the wiring terminal elements of switches of the aforementioned character.

Another object is to provide an improved arrangement affording better spacing between or insulation of all parts of the contact and terminal members of opposite polarity, to thereby better insure against surface creepage incident to the presence 01 metal dust and .the like in the atmosphere in which the switch may be employed.

A more specific object is to provide a snap switch having a novel form of rearor bottomwiring terminal elements;

Another object is to provide a rear-wired snap switch having novel means for attaching or supporting the neutral wire of a three-wire source of current supply.

Another object is to provide an arrangement of wiring terminals to enable selective employment of a greater variety of switch supporting v and actuating elements.

Another object is toprovide an insulating base normally adapted to provide a switch for use with a two-wire source of current supply, and readily adaptable for attachment of the neutral wire terminal member to provide a switch for use with a three-wire source of current supply.

Another object is to provide a snap switch of the aforementioned character affording more complete closure of the switch chamber or recess with respect to the surrounding atmosphere.

Another object is to provide alternative forms of neutral wire terminal elements, which maybe selected for use on the switch according to the wiring space afiorded in the casing of the tool with which the switch is to be employed.

Another object is to generally improve the details of construction of the switch parts whereby the operating life of the switch is substantially increased.

Another object is to provide novel forms of switch supporting members and novel forms of switch actuating elements to be'associated therewith.

Other objects and advantages of the invention will hereinafter appear.

The accompanying drawings illustrate certain embodiments of the invention which will now be described, it being understood that the illustrated embodiments are susceptible of modification in respect of certain details of construction thereof without departing from the scope of the appended claims.

In the drawings, Figure l is a top plan view of one form of electric snap switch constructed in accordance with my invention. 5

Fig. 2 is a vertical sectional view, on the line 22 of Fig. 1.

Fig. 3 is a bottom plan view of the switch shown in Figs. 1 and 2,--the supporting top plate and the insulating cover plate being omitted.

Fig. 4 is a vertical sectional view, substantially on the line 4-4 of Fig. 3, with the insulating cover plate shown in position thereon.

Fig. 5 is a view similar to Fig. 3, but showing a modified form of means for attachment and support of the neutral wire of a three-wire source of current supply.

Fig. 6 is a side elevational view, with parts in vertical section, showing switch parts like those illustrated in Fig. 5 employed in conjunction with 20 switch supporting and actuating elements of modified form.

Fig. 7 is a top plan view of the switch shown in. Fig. 6.

Fig. 8 is a fragmentary vertical sectional view, on the line 8-8 of Fig. 5..

Fig. 9 is a bottom plan view (double size) of a molded insulating base which may be utilized in producing the switches shown in Figs. 1 to 8,-- the bottom wall of the switch chamber, however, being shown closed to provide for omission of the neutral wire terminal member.

Fig. 10 is a vertical sectional view, on the broken line Ill-Ill of Fig. 9.

Fig. 11 is a plan view of the sheet metal blank from which the switch supporting plate of Figs. 1 and 2 may be formed.

Fig. 12 is a fragmentary sectional view similar to Fig. 8,but showing means for insuring complete closure of the bottom wall of the switch chamber in the absence of the neutral wire terminal screw,and to further insure against use of a terminal screw having a shank of excessive length.

Fig. 13 is a fragmentary sectional view similar to Fig. 12,-but showing a two-screw auxiliary terminal plate of a length to lie within the width of the switch base,--as distinguished from that shown in Figs. 1 to 4.

Fig. 14' is a top plan view of the switch base, and

Fig. 15 is an enlarged perspective view of the switch-actuating guide link shown in Figs. 5 and "i.

The switches herein disclosed embody certain features of the switches described and claimed in my prior patents, No. 1,889,259, dated November 29, 1932, and No.. 1,977,078, dated October 16, 1934.

Referring first to the form of switch shown in Figsal to 4 and 11, the numeral 20 designates a base molded from a suitable insulating material, such as the phenol-formaldehyde condensation product sold commercially under the trade-name flat punched plate 25 of fiber or other suitable insulating material is adapted to slide. Plate 25 is of substantially rectangular form and ofa width to fit between and be guided by the side' walls of recess 2|. The length of plate 25 is sub- .stantially less than the length of recess 2|, and

the end walls of the latter are adapted to limit movements of the former to opposite extreme positions,--said plate 25 being cut away at opposite ends thereof (Fig. 2) to accommodate the respective end ribs 23 and. 24 aforementioned.

Plate 25 is provided with a symmetrically arranged longitudinally extending slot or opening 26 (Fig. 2) which is adapted to accommodate, with a lost motion, the lower end of an oscillatable member 21 which is preferably formed of insulating material. Member 21 is pivotally supported by a U-shaped wire yoke member 28, which is in turn pivotally supported in a'pair of alined openings 29 and 30 formed in the upstanding parallel arms 3| and 32' of a supporting top plate 33, the blank for which is shown in Fig. 11. Plate 33 is bent along the four parallel dotted lines shown in Fig. 11 to the form shown in Figs. 1 and 2,-the base portion 34 of said plate being provided with a pair of tapped openings 35, 36 to accommodate the shanks of a pair of securing screws 31 and 33. A second pair of tapped openings 39 and 49 is preferably provided to enable alternative use of a switch base (not shown) of relatively smaller dimensions.

Plate 33 is provided with an opening 4| which preferably extends to a slight degree into the area of each of the arms 3|, 32 (Fig. 11) to facilitate upward bending of the latter,said opening 4| providing clearance forthe upper. end of a coiled compression spring 42 (Fig. 2) and for the abutment end of a lever 43, which engages a metal cup 42* positioned within said end of the spring. The lower end of spring 42 is adapted to telescope onto the upper end of member 21 (Fig. 2) and to abut a pair of shoulders formed on the latter. The oppositely extending'horizontal arms of top plate 33 are respectively provided with openings 33, 33 through which suitable screws or bolts (not shown) may pass for clamping the complete switch unit to a suitable support.

. Lever 43 is preferably embedded or 'molded' within a die cast metal handle or lever oi the form shown at ,44 in Figs. 1 and 2. Plate 33 is provided with lugs 45 and 46 which extend upwardly in the respective planes of the arms 3| and 32,-said lugs being provided with alined openings to receive the headedpin 41, the shank of which penetrates handle .44 and lever 43 and is spread or'upset, as shown at41, Fig. 1, to' hold the lever in assembled relation to the top plate.

Handle 44 is preferably provided with a recess or cavity 44, Fig. 2, to accommodate a coiled compression spring 48. In practice the extrusion surrounding the aforementioned tapped opening 39 is utilized as an abutment for the lower end of said spring. The arrangement is such that handle 44 is normally biased in a counter-clockwise direction (Fig. 2) to effect (through spring 42, yoke 28 and member 21) snap movement of plate 25 from its right-hand position to its lefthand'position -manual operation of lever 44 in a clockwise direction obviously providing for snap movement of plate 25 from left to right.

The stationary and movable contact elements of the switch are in general'quite similar to those illustrated in my Patents Nos. 1,889,259 and 1,- 977,078 aforementioned. In Fig. 4 I have shown one pair of lower and upper stationary contacts 49 and 50 between the resilient tips of which the ter,it being understood that in each of the switches herein disclosed the use of two pairs of upper and lower stationary contacts is contemplated. The plate 25 .is notched at the midpoint of each side edge thereof to receive the connecting portions of a pair-of similarly arranged movable bridging contactors, one of which is shown at in Fig. 4.

The arms of said contactors preferably extend to a line substantially flush with one end of plate 25, and said arms and the plate are pro vided with alined openings to receive the shanks of headed rivets,'on'e of which is shown at 5|, the shank ends of said rivets being upset as shown to rigidly and permanently secure the contactors to plate 25. A relatively thin plate 52 of fiber or other insulating material is loosely positioned above the tips of the aforementioned pairs of stationary contacts, but below the yoke member 28 and spring 42, to afford a substantially closed and relatively restricted arcing chamber,--said plate 52'having a slot 52* (Fig. 2) formed therein to provide clearance for member 21 during oscillating and bodily movement of the latter.

As illustrated in Figs. 4, and 14, base 29 is provided at the four corners thereof with substantially rectangular recesses 53, 54, 55 and 56 which are respectively adapted to receive with a fairly snug fit the rectangular ends of the stripmetal stationary contacts.

Base 20 is provided with passages 53, 54 55 and 55 of circular cross section which extend from the lower surface 2|) of said base and open to the respective recesses.

As best illustrated in Figs. 9 and 10 each of said passages is provided at its lower end with an enlargement or countersink 53 54 55 56 of square or other polygonal contour, to accommodate the correspondingly shaped heads of internally threaded hollow metal members or eyelets, two of which are shown at 58 and 59 in Fig. 4, another of which is shown in dotted lines at 60 in Fig. 3, and the other of which is shown at 6| in Fig. 5. The shanks of said eyelets penetrate openings in the aforementioned ends of the contacts and the plates 51 and are upset over the latter, as shown: at 58' and 59* in Fig. 4. Although I prefer to attach said eyelets to the base in the manner illustrated and described, it is of course to be understood that the same might be arranged in the reverse manner, with the shank Superimposed upon said ends of the contacts (see Fig. 4) are metal plates or washers 51 (preferably square).

In practice, after attachment of the two lower contacts (such as 43) of the switch, the plate 25. with the contactors attached thereto isinserted in the relationship illustrated, and thereafter the two upper contacts (such. as are secured to base 20 (see Fig. 4). The aforementioned. eyelots are threaded internally throughout the major portion of the length thereof, and I prefer to employ binding screws 58 59?, 60 and 6U the screws Bi and 60 shanks of which are-relatively long,as shown in Fig. 4. The circuit wires (not shown) may be clamped directly against the eyelet heads(see ii in Fig. 5) by the heads of the respective binding screws. of said binding screws a flat plate 62 of the form best illustrated in Figs. 3 and 4,the lower surface 2!] of base 20 having correspondingly shaped shallow recesses to accommodate said plates in a substantially flush relationship to said surface. Moreover, each plate 62 is preferably provided at its outermost end with a lug or flange 62 which is angled away from the bottom surface 20* of the base to provide a guard for facilitating and insuring proper attachment of a circuit wire.

As best illustrated in Fig. 2 I prefer to interpose between the upper surface of base 20 and the supporting top plate 33 a flat punched plate 63 of laminated fiber or similar insulating material,-said plate having a substantially circular opening I53 formed therein to provide clearance for the yoke 28 and spring 42. Plate 63 is also provided with openings to afford clearance for the shanks of screws 31, 38 which engage with the aforementioned tapped openings 35 and 36.

in top plate 33. The spring 48 is preferably assembled with respect to handle 44 and top plate 33 prior to insertion of the aforementioned pivot pin 41. It is to be understood, however, that spring 48 may be inserted or removed after said handle is pivotally attached to the top plate. Handle 44 is preferably formed as indicated at 44 and 44 to provide ample clearance between the same and the securing screws 3| 'and 38.

As shown in the several figures of the drawings (particularly Figs. 2, 4, 6, and 14) the upper surface of base is unbroken throughout the periphery thereof wherefore the insulating plate 63 which overlies the same (Fig. 7) provides an effectual seal to prevent ingress of dust particles into the switch chamber,--the aforementioned opening 63 in said plate being substantially covered or protected by the cover plate 33 and the switch operating elements carried thereby.

' The bottom surface 2i) of base 20 has formed integrally therewith a pair of longitudinally extending barriers 64 and 65, and a pair of spaced transversely extending barriers 6B and 6'I,the barriers 64 and 66 being merged and the barriers 65 and 61 being merged,thus providing five areas upon said bottomsurface which are insulated from each other. When the motor to be controlled by the switch is fed from an ordinary two-wire source of supply, the severed ends of one of the supply wires are respectively attached to the switch by means of screws 58 and 59 and the severed ends of the other supply wire are respectively attached to the switch by means of When the switch is to be used for control of a two-wire source of supply, the bottom wall of recess 2| in base 20, which is preferably initially molded in the manner best illustrated in Figs. 9, 10 and 14, is left imperforate to insure against entrance of dust or other foreign matter into the switch chamber.

When the switch is to be used for control of I prefer, however, to associate with each current from a three-wire source of supply it is necessary or desirable to bring the three wires (including the neutral wire) to the switch base. I therefore provide neutral wire terminal means upon the switch base. For this purpose the relatively thin circular area 'Hl (Figs. 10 and 14, and shown in dotted lines in Fig. 9) is broached out to accommodate the hollow cylindrical of a rivet 65* (Fig. 2); the square closed head 35 of which is accommodated within 9. correspondingly shaped recess 68 in the bottom wall of recess 2|. The depth of the head 65 of said rivet (Fig. 2) is preferably such that the upper surface thereof is substantially flush with or below the bottom wall of the auxiliary recess 68 which provides clearance for the aforementioned member 21.

In Figs. 1 to 4 I have shown a terminal plate 69 which is adapted to seat against the flat surface 10 (Fig. 9) offset downwardly from the aforementioned bottom surface Zo -of the base,- said plate being located between the aforementioned transverse barriers 66 and 61, and the same having upwardly oiiset end portions 69* and 69* which project beyond opposite sides of base 20. Said end portions 69 and 69 are provided with tapped openings to receive the shanks of binding screws 69 and 69 in a relation to clear the opposite sides of base 20 (see Fig. 1). Plate 69 is provided with an intermediate opening to receive the shank of rivet 65*,which is upset as shown in Figs. 2 and 3 to secure the plate to base 20. The shoulders formed by oilsetting portions 69 and 69 of plate 69 and the adjacent ends of the barriers 66 and 61 act as wire-beard guards to facilitate attachment of the circuit wires to said plate.

In Figs. 5 and 8 I have shown a modified form of switch adapted to provide for attachment ofthe neutral wire of a three-wire source of current supply, as by means of a single binding screw H. For this purpose I may employ an internally threaded hollow member or eyelet 12 (Fig. 8) over the projecting end of which a washer I3 (preferably circular) is adapted to fit,--said projecting end being then upset as shown at 'I'l to retain the eyelet in position. A portion of the neutral wire (not shown) may be" bared and formed into a loop of suitable size to be clamped against the upset end'lZ of the eyelet by the head of screw 'Il. As an alternative, the neutral wire may be cut and the respective cut ends thereof bared for clamping by the head of screw H. As will be noted the shank of screw H is made sufliciently short to avoid any possible interference between the same and the member 21 which moves within the auxiliary recess 68.

In Fig. 12 I have shown an arrangement quite similar to that of Fig.8. In this instance, however, -I' employ an internally threaded hollow member or rivet 14 having a closed upper end,- the shank 14 of which is upset over washer 13.

By employing a closed-end member I positively insure that a binding screw, such as 15, having a sufficiently short shank will be employed. .By the arrangement shown in Fig. 12 the screw I5 maybe entirely omitted (in the event that the necessitate positioning of the neutral wire bindto opposite ends thereof with tapped openings to receive the shanks of binding screws 11 and 18 of suitable length. Plate 16 is provided with an intermediate opening through which the hollow end of a solid-headed rivet 19 is adapted to pass,-said hollow end being upset as shown at l9 to rigidly secure plate Hi to base 29. In practice the plate 19 is of a width substantially equal to the widthof plate 69 (Fig. 3) whereby the same fits rather snugly between the aforementioned barriers 66 and 6'! on the'bott'om'surface 29 of the base. I

In Figs. 6, '7 and 15 I have illustrated a switch having supporting and actuating means of modified form. The insulating base 29 is like that aforedescribed, and it is to be understood that the stationary and movable switch contacts and switch contacts is reversed in position, with rethe terminal members may be'identical with the parts aforedescribed. It is to be noted, however, that base 29 with its stationary and movable spect' to the arrangement of Figs. 1 to 5. In Fig. 6 I have shown neutral wire terminal connecting means of the character illustrated in Figs. 5 and 8, but it is obvious that any of the other neutral wire terminal means may be employed alternatively, or the same may be omitted entirely (see Fi 9) where the switch is to be used for control of a two-wire source of current supply.

The switch supporting means comprises essentially a metal top plate or member having a portion ill of inverted channel shape in cross with openings to pivotally support the opposite ends of yoke member 29. Portion 86 is provided with a pair of tapped openings 82 and 83 to receive the shanks of screws 89 and 95, which secure said top plate to base 29. Portions 8! is likewise provided with a pair of less widely spaced tapped openings 88 and 8?, to provide for use of the top plate 89 with a relatively smaller insulating-base (not shown) or alternatively, to accommodate securing screws for attaching the switch unit to a suitable support.

Top plate 89 is provided at the forward end thereof with integral extensions 99 and 89 located in parallel vertical planes, the upper edges of said extensions being inclined upwardly, and said edges being connected by the portions 99 and 98 to form a substantially rigid frame. A manually operable lever 92 of substantially saddle form is adapted to straddle extensions 98 and 89 and is permanently pivotally secured thereto as by means of a headed pin 93, the shank end of which is upset over the side 92 of lever 92 to retain said pin in position. The parallel side portions 92*- and 92 of 'lever 92 are provided with alinec. openings to receive the headed pin or rivet 94, the shank end of which is upset as shown at 99 (Fig. 7). Pin 99 likewise penetrates ali ned openings in the forward ends of the parallel arms 95 (Figs. 6 and 15) of a switch-actuating guide link 99. The top edges of said arms 95, 95 are connected by integral flat portions 95, 95 said link having a cut-away portion or opening 95 to provide clearance between the same and the shank of screw 84 (Fig. 6).

Upon counter-clockwise movement of lever 92 (Fig. 6) the pivot pin 94 moves toward the downwardly projecting abutment 95 which fits within the cup 42 in the upper end of spring 42, whereby upon such movement of link. 95 the spring 42 is compressed to eifect storage of sumcient energy'to effect snap movement of the movable contactors to circuit completing position, as an incident to movement of the upper end of spring 42 to the right beyond the point of pivotal 92 spring 96 will act in an obvious manner to effect return of the switch parts to the respective positions thereof shown in Figs. 6 and 'l.

I have. shown means forlatching the switch mechanism in'circuit completing condition. Said means comprises a pin 99 having a shank 99 which is slidable within openings formed in the parallel arms 88 and 89 of the top plate extension. The outer surface of arm 89 (Fig. 6) is provided with an inward depression 89 surrounding the opening therein,said depression being adapted to accommodate a relatively thin washer 99*, over which the end of shank 99 is upset, to normally avoid interference between the shank 99 of said pin, with its attached washer, and the arm 92 of lever 92. The other arm 92 of lever 92 is provided with a relatively large opening 92 toprovide clearance between the same and shank 99 in all positions of said lever. However, the arm 92 of lever 92 is provided with an opening 92*, Figs. 6 and 7, which is adapted to register with shank 99 of the pin in the closed position of the switch. Under such conditions if pin 99 is pressed inwardly the aforementioned shank 99 and its associated washer will penetrate said opening 92 and thus restrain lever 92 from clockwise movement under the bias of spring 96.

A coiled compression spring 809 surrounds the shank 99 of said pin and is interposed under a predetermined degree of compression between the cylindrical head of pin 99 and the outer surface of arm 88 (Fig. 7). When the switch is thus latched in closed position, the same may be released by simply moving the lever 92 manually to its extreme counter-clockwise position, with reference to Fig. 6, so that the aforementioned washer may be withdrawn through the opening 92 by the action of the retracting spring I99. Thereafter, upon manual release of lever 92 the spring 96 will be free to act in the aforedescribed manner to return the switch parts to circuit interrupting position.

Outward movement of the guide link 99 is preferably limited by engagement of the end wall 95 of the opening 99 therein with the annular flange 86 (Fig. 6) surrounding the opening 86. Movement of link 95 in the reverse direction under the action of spring 99 is preferably limited by engagement of the lower portion of lug 99 of said link with the aforementioned shank 99 of pin 99.

the top surface of insulating base 29 at one endof the latter,said portion 99 having openings ZUU. ELEUIRICITY- CIRCUIT MAKERS & BREAKERS,

89 and- 89* to accommodate'suitable bolts: or other securing means whereby the unit as a whole may be attached to the casing of a power-operated tool, or to any other suitable support.

;-What I claim as new and desire to secure by Letters Patent is:

1. In an electric snap switch, in combination, a molded insulating base having a recess opening to the upper surface thereof, a plurality of pairs of resilient stationary contacts, the tips of each pair of stationary contacts being biased toward each other in spaced relationship to the bottom wall of said recess, a flat plate of insulating material interposed between and adapted to slidably engage the tips of the respective pairs of contacts in all positions of said plate, contactors carried by said plate and movable thereby into and out of bridging relation to said pairs of contacts, a yoke member pivotally supported for oscillatory movement of the lower end thereof within said recess, manually operable means including a coiled compression spring for effecting snap movement of said yoke member from each extreme position thereof to the other, means providing a lost motion driving connection between said yoke member and said insulating plate, a flat punched plate of insulating material superimposed upon the upper surface of said base and adapted to seal the peripheral upper edge of said recess, a plurality of wiring terminal elements comprising internally threaded hollow metal members having shoulders engaging the bottom surface ofsaid base and having shoulders engaging the respective contacts to secure the latter in position, and a corresponding number of binding screws having threaded engagement with said terminal elements, said screws having the heads thereof exposed upon said bottom surface of the base.

2. In an electric snap switch, in combination, a molded insulating base having a recess opening to the upper surface thereof, a plurality of pairs of resilient stationary contacts, the tips of each pair of stationary contacts being biased toward each other in spaced relationship to the bottom wall of said recess, a flat plate of insulating material interposed between and adapted to slidably engage the tips of the respective pairs of contacts in all positions of said plate, contactors carried by said plate and movable thereby into and out of bridging relation to said pairs of contacts, a yoke member pivotally supported for oscillatory movement of the lower end thereof within said recess, manually operable -means including a coiled compression spring for effecting snap movement of said yoke member from each extreme position thereof to the other, means providing a lost motion driving connection between said yoke member and said insulating plate, a fiat punched plate of insulating material superimposed upon the upper surface of said base and adapted to seal the peripheral upper edge of said recess, a plurality of wiring terminal elements comprising internally threaded hollow metal members extending upwardly from the bottom surface of said base and having the upper ends thereof upset over the respective contacts to secure the latter in position, a corresponding number of binding screws having threaded engagement with said terminal elements, said screws having the heads thereof exposed upon said bottom surface of the base, and said bottom Wall of said base having a plurality of barriers formed integrally therewith and interposed bew n said n n screws to insulate the latter from each other,

3; In an" electric switch, incombination, a molded insulating base having a recess formed therein and opening to the upper surfacethereof, stationary and movable contact elements located within said recess, said base having. a plurality of ledges ofiset downwardly from the upper surface thereof, said stationary contacts having flat portions adapted to seat upon said ledges respectively, a flat punched insulating plate seated upon the upper surface of said base and adapted to overlie said stationary and movable contact elements, a stamped sheet metal supporting member positioned above said plate and rigidly attached to said base, the outer surfaces of the side and end walls of said base being uninterrupted and the same being free from conducting elements, a plurality of internally threaded hollow metal members penetrating said base and positively restrained against rotation with respect thereto, said members having heads formed at each end thereof to respectively engage the bottom surface of said base and the flat portions of the contactors to secure the latter in position, and a corresponding number of binding screws having threaded engagement with said hollow metal members and being accessible from said bottom surface.

4. In an electric switch, 'in combination, a molded insulating base having a recess formed therein and opening to the upper surface thereof, stationary and movable contact elements located within said recess, said base having a plurality of ledges offset downwardly from the upper surface thereof and inwardly with respect to the peripheral side and end walls thereof, said stationary contacts having flat portions adapted to seat upon said ledges respectively, a flat punched insulating plate seated against the peripheral upper edge of said base and adapted to overlie said stationary and movable contact elements, a stamped sheet metal supporting member positioned above said plate and rigidly attached to said base, the outer surfaces of the side and end walls of said base being free from conducting elements, a plurality of internally threaded hollow metal members penetrating said base and positively restrained against rotation with respect thereto, said members having shoulders formed at each end thereof to respectively engage the bottom surface of said base and the flat portions of the contacts to secure the latter in position, a corresponding number of binding screws having threaded engagement with said hollow metal members and being accessible from said bottom surface, and said bottom surface having a plurality of relatively high longitudinally extending and transversely extending ribs formed integrally therewith and adapted to properly insulate said binding screws from each other.

5. In an electric, snap switch, in combination, a molded insulating base having a substantially rectangular recess formed therein and opening to the upper surface thereof, said base having ledges offset downwardly from the upper surface thereof and positioned within the continuous peripheral edge of the latter, said ledges communicating with said recess at the four corners respectively of the latter, two pairs of upper and lower resilient stationary contacts having flat portions thereof respectively positioned upon said ledges, the tips of said'pairs of contacts being located within said recess and biased toward each other, a movable insulating plate continuously interposed between the respective pairs of contact tips, a pair of contactors carried by said plate and movable thereby into and out of bridging engagement with said pairs of contact tips, flat metal members superimposed upon the fiat portions of said stationary contacts respectively, said flat metal members, said flat portions of said contacts and said base having alined openings formed therein, wiring". terminal members comprising a plurality of metal eyelets having head portions of angular contour adapted to seat within correspondingly shaped'r'ecesses in the lower surface of said base and shank portions adapted to penetrate each of said groups of alined openings, said shank portions having their ends upset over the respective flat members to rigidly secure said contact and terminal members to said base and to each other, said eyelets having internal threads formed therein, and a corresponding number of binding screws adapted to thread into said eyelets from the lower surface of said base.

6. In an electric snap switch, in combination, a molded insulating base having a substantially rectangular recess formed therein and opening to the upper surface thereof, said base having ledges offset downwardly from the upper surface thereof and positioned within the continuous peripheral edge of the latter, said ledges communicating with said recess at the four corners respectively of the latter, two pairs of upper and lower resilient stationary contacts having flat portions thereof respectively positioned upon said ledges, the tips of said pairs of contacts being located within said recess and biased toward each other, a movable insulating plate continuously interposed between the respective pairs of contact tips, a pair of contactors carried by said plate and movable thereby into and out of bridging engagement with said pairs of contact tips, fiat metal members superimposed upon the flat portions of said stationary contacts respectively, said fiat metal members, said flat portions of said contacts and said base having alined openings formed therein, wiring terminal members comprising a plurality of metal eyelets having head portions of polygonal contour adapted to seat within correspondingly shaped recesses in the lower surface of said base and shank portions adapted to penetrate each of said groups of alined openings, said shank portions having their ends upset over the respective flat metal members to rigidly secure said contact and terminal members to said base and to each other, said eyelets having internal threads formed therein, a corresponding number of binding screws adapted to thread into said eyelets from the lower surface of said base, and said insulating base having a plurality of relatively high longitudinally extending and transversely extending barriers formed integrally with the bottom surface thereof, to thereby minimize sur face creepage of electric current from each of said wiring terminal members to other of the same.

7. In an electric snap switch, in combination, a molded insulating base having a recess formed therein and opening to the upper surface thereof, two pairs of upper and lower resilient stationary contacts, the tips of each pair of stationary contacts being biased toward each other in spaced relationship to the bottom wall of said recess, a flat plate of insulating material interposed between and adapted to slidably engage the tips of the respective pairs of contacts in all positions of said plate, contactors carried by said plate and movable thereby into and out of bridging relation to said pairs of contacts, manually operable means including a coiled compression spring for effecting snap movement of. said. CQ IW QWIS f m each'extremeposition thereof to the other, a plurality of wiring terminal elements comprising in-- ternally threaded hollow metal members the shanks of which extend upwardly from the bottom surface of said base and are upset over the respective contacts to secure the latter in position, a corresponding number of binding screws having threaded engagement with said members and being accessible from said bottom surface of the base, and an auxiliary wiring terminal element, secured to the bottom surface of said base, said last mentioned element having at least one binding screw associated therewith to provide for attachment of the neutral wire of a three-wire source of current supply.

8. In an electric snap switch, in combination, a molded insulating base having a recess formed therein and opening to the upper surface thereof, two pairs of upper and lower resilient stationary contacts, the tips of each pair of stationary contacts being biased toward each other in spaced relationship to the bottom wall of said recess, a flat plate of insulating material interposed between and adapted to slidably engage the tips of the respective pairs of contacts in all positions of said plate, contactors carried by said plate and movable thereby into and out of bridging relation to said pairs of contacts, manually operable means including a coiled compression spring for effecting snap movement of said contactors from each extreme position thereof to the other, a plurality of wiring terminal elements comprising internally threaded hollow metal members the shanks of which extend upwardly from the bottom surface of said base and are upset over the respective contacts to secure the latter in position, a corresponding number of binding screws having threaded engagement with said members and being accessible from said bottom surface of the base, an auxiliary wiring terminal element secured to the bottom surface of said base, said last mentioned element having at least one binding screw associated therewith to provide for attachment of the neutral wire of a three-wire source of current supply, and said bottom surface of the base having a plurality of longitudinally extending and transversely extending barriers formed integrally therewith, said barriers being adapted to insulate said first mentioned terminal elements from each other and from said auxiliary terminal element.

9. In an electric snap switch, in combination, a molded insulating base having a recess formed therein and opening to the upper surface thereof,

a one-piece metal cover member of inverted channel-shape secured to the upper surface of said base, a flat plate of insulating material interposed between said cover member and said base, said cover member having integral parallel portions thereof extending beyond one end of said base and respectively located above the plane of the upper surface of said base, a manually operable lever pivotally supported by said parallel extending portions of the cover member, a guide link of inverted channel-shape slidable between said cover member and said insulating plate and having an operative connection with said lever, said link having an abutment formed at one end thereof, a coiled compression spring having an operative connection with said abutment to provide for snap movement of the switch contacts relatively to each other, a single coiled tension spring attached at one end to said cover member and at the other end to said guide link to bias the latter and said lever to given extreme positions, one of said parallel portions having an integral downward extension and said downward extension having a plurality of openings formed therein to provide for attachment of the switch as a unit to a suitable support.

10. In an electric snap switch of the character described, in combination,. a molded insulating base having a recess formed therein and opening to the upper-surface thereof, two pairs of upper and lower resilient stationary contacts, the tips of'each pair of contacts being biased toward each other in spaced relationship to the bottom wall of said recess, a fiat plate of insulating material continuously interposed between the tips of the respective pairs of contacts, contactors carried by said plate and movable thereby into and out of bridging engagement with sa d pairs of contact tips, means for securing said contacts to saidv base, said means comprising a corresponding number of internally threaded tubular metal members having heads of polygonal contour adapted to seat within correspondingly shaped recesses in the bottom surface of said base, the shanks of said members being upset over the respective contacts to secure the latter to said base, a corresponding number of binding screws having threaded engagement with said members and being accessible from said bottom surface of said base, a one-piece metal top plate superimposed upon the upper surface of said base and secured thereto, a flat plate of insulating material interposed between said top plate and said base, and said top plate having in integral portion thereof extending forwardly and downwardly in a vertical plane at right angles to one end of said base, saidportion having openingsformed therein 'to provide for attachment of the switch as a unit to a suitable support.

' 11. In an electricsnap switch of the character described, in combination, a molded insulating base having a recess formed therein and opening to the upper surface thereof, two pairs of upper and lower resilient stationary contacts,'

the tips of each pair of contacts being biased toward each other in spaced relationship to the bottom wall of said recess, a fiat plate of insulating material continuously interposed between the tips of the respective pairs of contacts, contactors carried by said plate and movable thereby into and out of bridging engagement with said pairs of contact tips, means for securing said contacts to said base, said means comprising a corresponding numberof internally threaded tubular metal members having shouldered portions of polygonal contour adapted to seat within correspondingly shaped recesses in the bottom surface of said base, the shanks of said members having shoulders engaging the respective contacts to secure the latter to said base, a corresponding number of binding screws having threaded engagement with said members and being accessible from said bottom surface of sa d base, a one-piece metal top plate superimposed upon the upper surface of said base and secured thereto, said top plate having a portion of inverted channel-shape, a flat plate of insulating material interposed between said top plate andflsaid base, a guide link of inverted channelshape slidable between said insulating plate and said top plate and projecting beyond one end of said base above the upper surface of the latter, said guide link having a spring abutment at the inner end thereof, a coiled compression spring interposed between said abutment and a part associated with said first mentioned insulating plate base having a recess formed therein and opening to the upper surface thereof, two pairs of upper and lower resilient stationary contacts, the tips of each pair of contacts being biased toward each other in spaced relationship to the bottom wall of said recess, a flat plate of insulating material continuously interposed between the tips of the respective pairs of contacts, contactors carried by said plate and movable thereby into and out of bridging engagement with said'pairs of contact tips, means for securing said contacts to said base, said means comprising a corresponding number of internally threaded tubular metal members having shouldered portions adapted to seat against the bottom surface of said base, the shanks of said members having shoulders engaging the respective contacts to secure the latter to said base, a corresponding number of binding screws having threaded engagement with said members and being accessible from said bottom surface of said base, a one-piece metal top plate superimposed upon the upper surface of said base and secured thereto, said top plate having a portion of inverted channel-shape, a flat plate of insulating material interposed between said top plate and said base, a guide link of inverted channel-shape slidable between said insulating plate and said top plate and projecting beyond one end of said base above the upper surface of the latter, said guide link having a spring abutment formed at the inner end thereof, a coiled compression spring interposed between said abutment and a part associated with said first mentioned insulating plate whereby snap movement of the latter is effected, said top plate having integral parallel vertical portions thereof extending beyond the aforementioned end of said base, a lever pivotally supported by said extending portions, said lever having a pivotal connection with said guide link, means comprising a single coiled tension spring associated with said top plate and said guide link to bias each of the movable parts of the switch to a given extreme position, and means comprising a pin carried by said parallel vertical portions of said top plate extension, said pinbeing manually operable to engage said lever in a given position thereof to restrain the same and said link against movement under the'biasof said tension spring.

13. In an electric snap switch of the character described, in combination, a molded insulating base having a recess formed therein and opening to the upper surface thereof, two pairs of upper and lower resilient stationary contacts, the tips of each pair of contacts. being biased toward each other in spaced relationship to the bottom wall of said recess, a flat plate of insulating material continuously interposed between the tips of the respective pairs of contacts, contactors carried by said plate and movable thereby into and out of bridging engagement with said pairs of contact tips, means for securing said contacts to said base, said means comprising a corresponding number of internally threaded tubular metal members having shoulders adapted to seat against the bottom surface of said base,

the shanks of said members having shouldersengaging the respective contacts to secure the latter to said base, a corresponding number of binding screws having threaded engagement with said members and being accessible from said bottom surface of said base, a one-piece metal top plate superimposed upon the upper surface of said base and secured thereto, said top plate having a portion of inverted channel-shape, a fiat plate of insulating material interposed between said top plate and said base, a guide link of inverted channel-shape slidable between said insulating plate and said top plate and projectwith said top plate and said guide link to bias each of. the movable parts, ofthe switch to a given extreme position, means comprising a pin carried by'said parallel vertical portions of said top plate extension, said pin being manually operable to engage said-lever in, a given position thereof to restrain the same and said 'link against movement under the bias of said tension spring, and a coiled compression spring associated with said pin to provide for movement thereof out of latching position upona predetermined degree of manual operation of said lever.

14. In an electric switch, in combination, a molded insulating base of substantially rectangular contour having a recess opening to the upper surface thereof, the side and end walls of said base being uninterrupted, apiurality of pairs of resilient stationary contacts, the ,tips' of each pair of stationary contactsbeing biased toward each other in spaced relationship to the bottom wall of said recess. a flat punched plate of insulating material interposed between and adapted to slidably engage the tips of the respective pairs of contacts in all positions of said plate, contactors carried by said plate and movable thereby into and out of bridging relation to said 3 pairs of contacts, a flat punched 'plate of insulating material secured to the upper surface of said base and seated against the peripheral upper edge of the recess walls, actuating means extending above and below said last mentioned plate for effecting movement of said first mentioned plate in opposite directions respectively,-

resilient stationary contacts, the tips of each pair of stationary contacts being biased toward each other in spaced relationship to the bottom wall of said recess, a flat punched plate of insulating material interposed between and adapted to slidably engage the tips of the respective pairs of contacts in all positions of said plate, contactors carried by said plate and movable thereby into and out of bridging relation to said pairsof contacts, a fiat punched plate-of insulating material secured to the upper surface of said base and seated against the peripheral upper edge of the recess walls, actuating means extending above and below said last mentioned plate for effecting movement of said-first mentioned plate in opposite'directions respectively, a plurality of 'wiring terminal members electrically connected with the respective contacts and exposed upon the lower surface of said base in positively interlocked relationship to the latter, said wiringtercommodate the shanks of a corresponding number of binding screws, and said lower surface of said base having a plurality of barriers formed integrally therewith and interposed between the minal members having threaded passages to' acexposed portions of said wiring terminal membars to insulatethe latter from each other.

16. In an electric switch, in combination, a.

molded insulating base having a recess formed therein and opening to the upper surface thereof, relatively movable switch contacts located within said recess, a stamped sheet metal cover member secured't'o said base atthe upper surface thereof, a flat punched plate of insulating material interposed between said cover-member and said base, 'saidcover member'having integral parallel vertical portions. thereof extending beyond one end of said base and respectively located above the plane of the upper surface of said base, one

of said parallel vertical portions having a perforated downward extension to provide for attachment of the switch to a suitable support, a

manually operable lever pivotally supported by operative connection with said guide link fp provide for snap movement of the switch contacts relatively to each other; and a single coiled tension spring attached at one end to said cover member and at the other end to said guide link to bias the latter and said lever to given extreme positions respectively.

1'1. In combination, a stamped sheet metal cover member for electric snap switches of the.

tool-handletype, said cover member having parallel vertical portions extending from one end thereof, one of said parallel vertical portions having a perforated downward-extension to provide for attachment thereof to a suitable sup-' port, a manually operable lever pivotaily support ed by said parallel vertical portions of said extension,a sheet metallink slidably engageable with said cover member and with said parallel vertical portions to be guided thereby, said link having an operative connection with said lever, lugs carried respectively by said cover member and said link, a coiled tension spring positioned between said parallel vertical portions and having its ends attached to said lugs respectively,

and across connecting portion rigidly attached to said parallel vertical portions to assist in spacing and strengthening the latter, saidcross connecting portion being so arranged as to insure clearance for said spring under all conditions.

18. In combination, a one-piece sheet metal top plate for electric snap switches of the tool-handle type, said top plate having a portion of inverted channel-shape, a sheet metal link of inverted channel-shape slidable within the channel portion of said top plate and projecting beyond one end of the latter, said top plate having parallel vertical portions extending from the aforementioned end thereof to assist in guiding said link, a manually operable lever pivotally supported by said parallel vertical portions, said lever having a pivotal connection with said projecting portion of the link, means comprising a single coiled tension spring respectively attached to said top plate and to said link to bias the latter and said lever for movement thereof in a given direction, said link having an abutment formed at the inner end thereof for cooperation with a switch actuating spring, means comprising a bolt carried by said parallel vertical portions, said bolt being manually operable to engage said lever in a given position thereof to latch the same and said link against movement under the bias of said tension spring, I

and a coiled spring associated under compression with said bolt to provide for movement of the latter out of latching position upon a predetermined degree of manual operation of said lever.

19. In a switch actuating device, in combination, a metal top plate of substantially channelshape, said plate having a pair of spaced parallel arms projecting from one end thereof, a trigger lever of approximately saddle-shape adapted to straddle said arms and pivoted to the latter, a pivot pin carried by said trigger lever at the lower end of the latter and bodily movable thereby, said pivot pin being engageable with said arms to limit movement of said trigger lever in one direction, a punched and stamped sheet metal guide link positioned within the channel of said top plate and between the arms of the latter for movement with respect thereto, one end of said guide link being attached to said pivot pin and the other end thereof having an abutment for cooperation with a switch actuating spring, a coiled spring interposed between said top plate and said guide link to bias the latter and said trigger lever for movement thereof in said one direction, and

one of. said arms being formed to facilitate attachment of the device to a suitable support.

20. In a switch actuating device, in combination, a stamped sheet metal top plate of substantially channel-shape, said plate having a pair of arms of approximately triangular contour formed integrally therewith and projecting laterally and upwardly in parallel planes from one end thereof, a stamped sheet metal trigger lever of approximately saddle-shape adapted to straddle said arms and pivotally supported by the latter adjacent to the upper ends thereof, a movable sheet metal link positioned within the channel of said top plate and between the arms of the latter to be guided thereby, a pivot pin penetrating the lower end of said trigger lever and said link to provide for movement of said link by said lever, that portion of the link positioned within the channel of said plate carrying an abutment for cooperation with one end portion of a coiled compression spring, said top plate and one of said pair of arms being respectively provided with openings which are alternatively adapted for use to facilitate attachment of the device to a suitable support, said link having a lug extending upwardly from the end thereof adjacent to 'said pivot pin, said top plate having a lug formed integrally therewith between said arms at the inner ends of the latter, a coiled tension spring having hooked ends respectively attached to said lugs whereby said link and said lever are biased in one direction toward a given extreme position, means for latching said trigger lever against movement toward said extreme position, said means comprising a bolt extending transversely of and carried by said pair of arms, said bolt being arranged to normally provide clearance between the same and said trigger lever, said bolt being manually movable endwise in a given position of said trigger lever. other than the aforementioned extreme position of the latter, for cooperative engagement with said trigger lever, spring means associated with said bolt to bias the same toward its normal position, and a flange on said bolt engageable with said trigger lever under the conditions last mentioned to restrain said bolt against its bias.

7 GEORGE J. MEUER. 

